TypeScript in Depth · Generics · Lesson 9 of 16
Generic Interfaces
Concept
Generic Interfaces
Interfaces can also take type parameters, useful for reusable shapes like API responses.
By the end of this lesson
- Explain the core idea behind Generic Interfaces.
- Predict output before running a change.
- Test one realistic and one unusual input.
- Use the result to make the next decision.
How to study this page
- 1. Read one concept.
- 2. Change the example.
- 3. Run, compare, and explain.
- 4. Complete the challenge below.
Self-check before continuing
Without looking at the example, describe what changes when you modify one input in Generic Interfaces. Then reopen the editor and prove your explanation with a small test.
You are ready to continue when you can predict, test, and explain the result.
Your turn
Define a generic Box<T> interface with a single value: T property.
Loading editor…
Console